J Clin Neurol.  2012 Sep;8(3):170-176. 10.3988/jcn.2012.8.3.170.

Transesophageal Echocardiographic Findings Are Independent and Relevant Predictors of Ischemic Stroke in Patients with Nonvalvular Atrial Fibrillation

• Takashima
• Nakagawa K
• Hirai T
• Dougu N
• Taguchi Y
• Sasahara E
• Ohara K
• Fukuda N
• Inoue H
• Tanaka K

• KMID: 2287587
• DOI: http://doi.org/10.3988/jcn.2012.8.3.170

Abstract

BACKGROUND AND PURPOSE
Not only clinical factors, including the CHADS2 score, but also echocardiographic findings have been reported to be useful for predicting the risk of ischemic stroke in patients with nonvalvular atrial fibrillation (NVAF). However, it remains to be determined which of these factors might be more relevant for evaluation of the risk of stroke in each patient.
METHODS
In 490 patients with NVAF who underwent transesophageal echocardiography (TEE), we examined the long-term incidence of ischemic stroke events (mean follow-up time, 5.7+/-3.3 years). For each patient, the predictive values of gender, the CHADS2 risk factors (congestive heart failure, hypertension, age > or =75 years, diabetes mellitus, history of cerebral ischemia), the CHADS2 score, and the findings on echocardiography, including TEE risk markers, were assessed.
RESULTS
The ischemic stroke rate was significantly correlated with the CHADS2 score (p<0.05). According to the results of univariate analyses, age > or =75 years, history of cerebral ischemia, CHADS2 score > or =2, and presence of TEE risk were significantly correlated with the incidence of ischemic stroke. Cox proportional hazards regression analyses identified age > or =75 years and presence of TEE risk as significant predictors of subsequent ischemic stroke events in patients with NVAF. As compared with that in persons below 75 years of age without TEE risk, the ischemic stroke rate was significantly higher in persons who were > or =75 years of age with TEE risk (4.3 vs. 0.56%/year, adjusted hazard ratio=8.94, p<0.001).
CONCLUSIONS
TEE findings might be more relevant predictors of ischemic stroke than the CHADS2 score in patients with NVAF. The stroke risk was more than 8-fold higher in patients aged > or =75 years with TEE risk.

Keyword

stroke; risk; atrial fibrillation; transesophageal echocardiography

MeSH Terms

Aged
Atrial Fibrillation
Brain Ischemia
Diabetes Mellitus
Echocardiography
Echocardiography, Transesophageal
Follow-Up Studies
Heart Failure
Humans
Hypertension
Incidence
Risk Factors
Stroke

Figure

• 

  Fig. 1 A: Kaplan-Meier survival curves for ischemic stroke by the CHADS2 score in patients with NVAF. The incidence of ischemic stroke in patients with a CHADS2 score of less than 2 was 1.18% per year, while that in patients with a CHADS2 score of 2 or over was 2.19% per year (log-rank test, p<0.05). B: Kaplan-Meier survival curves for ischemic stroke according to the presence/absence of TEE risk in patients with NVAF. The incidence of ischemic stroke in patients without TEE risk was 0.67% per year, while that in patients with TEE risk was 2.26% per year (log-rank test, p<0.001). NVAF: nonvalvular atrial fibrillation, TEE: transesophageal echocardiography.

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  Fig. 2 Kaplan-Meier survival curves for ischemic stroke using the combination of age and TEE risk in patients with NVAF. The incidence of ischemic stroke was 0.56% per year in patients younger than 75 years of age without TEE risk, but 4.3% per year in patients aged 75 years or older with TEE risk (log-rank test, p<0.001). NVAF: nonvalvular atrial fibrillation, TEE: transesophageal echocardiography.

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